GAP Analysis Predicted Distribution Map

Barrow's Goldeneye (Bucephala islandica)

Species Code: BUIS

Legend: = Core Habitat = Marginal Habitat

Breeding Range Map
The green area shows the predicted habitats for breeding only. The habitats were
identified using 1991 satellite imagery,
Breeding Bird Atlas (BBA), other datasets and experts throughout the state, as part of the Washington Gap Analysis
Project. Habitats used during non-breeding months and migratory rest-stops were not mapped.

This species is common in larger ponds, lakes, and reservoirs at moderate and higher elevations in the Cascades, the Okanogan and
Methow valleys, and northeastern mountains and river valleys. A unique disjunct population occurs in the Columbia Basin at Lake
Lenore, where this species nests in cliff cavities (in the absence of tree cavities). Most of its range is east of the Cascade
crest, but it is often common where it occurs west of the crest. They are not found in the Blue or Olympic Mountains. They generally
prefer montane and sub-alpine lakes in forested areas and need cavities for nesting.

Good habitats in the core areas of use were fresh water/wetlands in the forested zones of eastern Washington, plus Silver Fir
and Mountain Hemlock in western Washington. Forests in these zones were included knowing there may be smaller pockets of habitat
suitable for them. Fresh water/wetlands in steppe zones where Barrow's Goldeneye breeds locally (but often abundantly) were also
good habitat in the core areas of use.

Barrow's Goldeneye is most common as a breeder in the Cariboo parkland region of central British Columbia. In Washington,
it mostly inhabits similar habitats in higher lakes. Of extra interest are the records of this species in the arid Columbia
Basin. Despite the lack of tree cavities for nesting, many confirmed breeding records come from Lake Lenore, which is surrounded
by shrub-steppe vegetation. The birds nest in crevices in the rocks and feed on the abundant invertebrates in the lakes. Records
of non-breeding birds are known from Potholes Reservoir and from various scabland ponds in Lincoln, Spokane, Adams, and Whitman
Counties. Barrow's Goldeneye are rare summer residents in the latter counties. They are curiously absent from Turnbull National
Wildlife Refuge as a breeder although it provides many large ponds, surrounded by trees, and is vegetative similar to the Okanogan
valley (which has many confirmed records).